Warp letoff motion



Feb. 17, 194

E.` KINSELLA wARP LETOFF MOTION Filed Nov. 27, 1940 s Smets-Sheet 1 INvlw-ro/f @im AWA/EU Feb. 17, 1942. E. KlNsELLA WARP LETOFF MOTION Filed Nov. 27, 1940 5 Sheets-Sheet 2 E-KINSELLA )Nus/v 1M @y A Tron/s 7s Feb. 17, 1942. E. KlNsELLA 2,273,325

WARP LETOFF MOTION Filed Nov. 27, 1940 3 Sheets-Sheet 3 mvsuToA Patented Feb. 17, 1942 WARP LETOFF MOTION Edward Kinsella, Spondon, near Derby, England, assignor to Celanese Corporation of America, a corporation of Delaware Application November 27, 1940, Serial No. 367,331

In Great Britain December 28, 1939 4 Claims.

This invention relates to improvements in Warp let-off motions. The let-off motion according to the invention is particularly Well adapted for use in circular looms designed for the production of dress fabrics and other high quality fabrics.

A warp let-off motion according to the invention comprises a warp-beam carriage movable in the direction in which the yarn leaves the beam, means to urge the carriage in a direction opposite to that in which the yarn leaves the beam, means for rotatably mounting a beam in the carriage, friction gearing in driving connection with the beam mounting, the gearing comprising a driver member adapted to be constantly rotated Yeither direction, and advantageously a wiper contact is provided by means of which a stop motion is rendered operative in the event of excessive movement of the carriage, especially under conditions of particularly high yarn tension.

With a sensitive fully-compensating let-olf mechanism of the character described above, and with the usual type of continuously-driven takeand a driven member movable to variable radial l5 up mechanism, a circular loom is enabled to distances with respect to the driver member, and Weave fabric of particularly high quality. In means connecting the beam carriage to the addition the let-oil mechanism is helpful in driven member to enable the radial `distance at avoiding bars in the fabric resulting from gradual Which the driven member contacts with the Stretch Of the yallfl during any fairly PlOlOIlged driver member to be governed by movements of stoppage of the loom. the beam carriage in response to Variations in A form of let-off mechanism according to the the tension of the yarn, invention as applied to a circular loom employ- The driving connection from the friction gearing four warp beams will now be described in ing to the beam mounting includes worm or other greater detail4 with reference to the accompanyreduction gearing to enable the beam to be roing drawings, in Which tated at the relatively slow rate necessary to de- Fi'gS- 1 and 2 are deglammatie plan and eleliver yarn at the rate at which it is consumed, vation views showing the general construction of while permitting the friction gearing to operate a circular loom. at an eoient speed, The friction gearing may Fig. 3 is an elevation to a larger scale of the conveniently be in driving connection with the let-Off meellelism tellen 011 the lille 3-*3 0f Fig. take-up motion, since let-off and take-up rates 4J and are necessarily correlated. Fia 4 iS a plan VieW 0f part Of Fig. 3.

By means of the motion according to the in- The Warp Supply iS placed 0H tOlI Of the 100m vention an increase in the yarn tension causes frame, Which comprises fOul Vertical Columns I the beam carriage to move so as to increase the tied rigidly together by an X-member 2. Brackradial distance at which the driven friction memetS 3 0n the 00111111115 DlOVCie a Sclid SllDlJOrt for ber contacts with the driver membery with the four rollers 4, over which the four warps are led result that the beam is driven et proportionately from the beams 5 and turned downwardly before increased speed. With the resultant increased being COlStlaiIled intO Cylindrical form Over the deiivery of yam from the beam, the yam tension vertical length 6 for the insertion of weft by the is reduced and the driven member returns toseveral shuttles of the loom, of which two are wards the centre of the driver member. Conse- Seen at l. The fabric 8 proceeds to the take-up quently, a constant adjustment of tension is promotion 9 at the foot of the loom. The four guide vided, notwithstanding the variation in the diamrollers 4 occupy the sides of a Square Within the eter of the body of yarn on the beam as Weaving Square bounded by the four columns I. The proceedswarp beams 5 are supported on brackets I0 In the case of a circular loom, weaving proformed by angle-irons II extending horizontally ceeds continuously round the circumference of beyOnCl the four columns. Each bracket IB carthe loom, and all the essential mechanisms reries a rail I 2 on which wheels I3 on the end ceive movements of simple rotation. Accordframe I4 of the beam carriage I5 run, the two ingly, therefore, the driver friction member for frames I 4 being connected by rods I6. Rotatable the let-off mechanism may be directly coupled to tubes I I surrounding the two lower rods I6 carry some suitable part of the main driving mechathe beam flanges and permit the beam to rotate nism of the loom to provide a continuously availeasily. able drive for the warp supply. At the outer end of each bracket I0 is secured a sprocket I8, over which passes a chain IS connected at 2B to one of the end frames I4. The chain I9 passes round a sprocket 2l pivoted on a shaft 22 on the bracket I0 and secured to a sprocket 23 of twice the diameter. The end of the chain i9 is secured at 24 to the sprocket 23. Another chain 25 secured to the sprocket 23 at 26 passes round the sprocket and carries removable weights 21.

The run of the chain I9 from the sprocket i8 to the point of attachment 20 to the beam carriage l is horizontal, at a height substantially midway between the heights at which the yarn leaves the top of the beam when the beam is full and empty respectively. The pull of the two chains at the ends of each beam carriage determines the warp tension, and the differential sprockets 2l, 23 permit small, easily handled weights 21 to be applied to the chain 25 to bring about the required tension.

Near one end frame M a worm wheel 23 is mounted and a detachable driving member 2S enables a warp beam 5 placed between the end frames to be rigidly connected to the worm wheel. A worm Sii mounted on a horizontal shaft 3i meshes with the worm wheel. The shaft 3l is connected by a flexible coupling $2 to a shaft 33 to the end of which is secured a friction wheel 34 whose edge makes contact with the face of a driver friction wheel 35 mounted on a vertical shaft 36 in a subsidiary frame 31 carried by the member 2. The four driver friction members 35 are driven by a single chain 3S passing round sprockets 39 on their respective shafts 35,

sprockets t9 on the member 2, and a sprocket 4l I on a vertical shaft B2 geared to the main loom mechanism through suitable adjustable reduction gearing G3. A universal coupling it on the shaft ft2 provides for the driving of the take-up motion 9, and a handwheel [i5 enables the letof and take-up motions to be operated by hand. The main drive shaft 42 rotates at such a speed that in conjunction with the reduction oiered by the worm gearing 28, 39 the requisite amount of yarn is let-oir when the driven friction wheels 3d are engaging an intermediate range of the surfaces of the driver friction wheels 35, the compensation provided being suiiicient in any case to deal with the dierent rates of angular rotation oi the warp beams necessary to allow for the diminishing diameter of the beam as weaving proceeds. IThe gear 43 included in the main shaft drive allows for a wide range of let-off rates.

Referring to Fig. 3, it will be apparent that if the tension in the warps increases, the pull of the warps between the roller and the beam 5 will move the carriage i4 to the right against the urge of tension of the chain I9 in the opposite direction. The shafts 3l, 33 also move to the right and the driven wheel 34 on the shaft 33 moves towards the periphery of the driver wheel 35. The wheel 34 is therefore driven faster and the rotation of the beam 5 increases correspondingly to deliver yarn at a greater rate towards the roller 4 until the tension is again balanced by the pull in the chain I9.

At the outer ends of the brackets IG stops 46 are provided to prevent over-running of the carriages in the event of a smash. Similarly, stops i1 may be provided at the inner ends of the brackets to limit the movement of the carriages in the event of excessive warp tension. However, in order to prevent damage to the warps one of each pair of brackets carries a contact strip 48 over which a wiper 49 moves, so as to break the connection between leads 50 and thereby operate a stop mechanism (not shown) in the event of excessive inward movement of the carriage. Hooks 5l depending from the end frames of the carriage prevent accidental lifting of the carriage from its rails I2. Strong safety chains 52 hanging loosely from the brackets l0 to the weights 21 prevent falling of these weights in the event of breakage of one of the chains connecting the weights to the carriage.

Having described my invention, what I desire to secure by Letters Patent is:

l, Warp let-off motion comprising a warpbeam carriage movable in the direction in which the yarn leaves the beam, means to urge the carriage in a direction opposite to that in which the yarn leaves the beam, means for rotatably mounting a beam in the carriage, friction gearing in driving connection with the beam mounting, the gearing comprising a driver member adapted to be constantly rotated and a driven member movable to variable radial distances with respect to the driver member, and means connecting the beam carriage to the driven member to enable the radial distance at which the driven member contacts with the driver member to be governed by movements of the beam carriage in response to variations in the tension of the yarn.

2. Warp let-off motion according to claim 1, comprising rails, and rollers on the beam carriage to enable the carriage to roll along the rails in response to variations in the tension of the yarn.

3. Warp let-off motion according to claim l, comprising rails, rollers on the beam carriage to enable the carriage to roll along the rails in response to variations in the tension of the yarn, and stops to limit the movement of the carriage along the rails.

Ll. Warp let-off motion according to claim l, comprising means to render a stop motion operative in the event of excessive movement of the beam carriage.

EDWARD KINSELLA. 

